A Study of LY2951742 in Healthy Volunteers

Inclusion Criteria: * Are healthy Caucasian males, as determined by medical history and physical examination * Agree to use a reliable method of birth control (e.g. condom AND additional contraception method to be used by respective partner) during the study and for 3 months following the last dose of the investigational product * Have a body mass index (BMI) greater than 19 kilogram/square meter (kg/m\^2) * Have clinical laboratory test results within normal reference range for the population or investigator site * Have venous access sufficient to allow for blood sampling * Are willing to follow study procedures including no drugs (exception of study drug) 72 hours prior to initiation of the laser doppler imaging (LDI) procedure, no chocolate, alcohol or caffeine containing products 12 hours prior to initiation of the laser doppler imaging (LDI) procedure, and complete a 4 hour fast prior to initiation of the laser doppler imaging (LDI) procedure * Have suitable skin characteristics for the dermal capsaicin challenge and have demonstrated a 100 percent increase in dermal flow following capsaicin challenge as part of the screening procedures and measured by laser doppler imaging (LDI) Exclusion Criteria: * Are currently enrolled in, have completed or discontinued within the last 30 days from, a clinical trial involving an investigational product; or are concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study * Are persons who have previously received the investigational product in this study, have completed or withdrawn from this study investigating LY2951742 * Have an abnormality in the 12-lead electrocardiogram (ECG) that, in the opinion of the investigator, increases the risks associated with participating in the study including QTc greater than 450 milliseconds (msec) (male), history of congenital long QT syndrome or other conduction abnormality * Have abnormal vital signs as determined by the investigator * Have a history or presence of significant cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, or neurological disorders (including migraine) that would constitute a risk when taking the study medication; or of interfering with the interpretation of data study * Regularly use known drugs of abuse and/or show positive findings on urinary drug screening * Show evidence of: 1. Human immunodeficiency virus infection and/or positive human immunodeficiency virus (HIV) antibodies 2. Hepatitis C and/or positive hepatitis C antibody 3. Hepatitis B and/or positive hepatitis B surface antigen * Intend to use over-the-counter or prescription medication that may interfere with study safety assessments or other measurements within 7 days prior to dosing and during the study (example: systemic glucocorticoids, immunomodulatory drugs, drugs with propensity for dermal reactions, and drugs with known liver toxicity). * Have donated blood of more than 500 milliliter (mL) or has undergone major surgery * The use of caffeine containing products and alcohol is not allowed from 12 hours prior to all study visits and during in clinic stays. All other times, alcohol consumption and caffeine intake are limited to no more than 2 alcoholic beverages or equivalent (beer \[284 mL/10 ounces\], wine \[125 mL/4 ounces\], or distilled spirits (25 milliliter \[mL/1 ounce\]) per day and caffeinated beverages will be limited to no more than 2 units per day amounts (1 unit=120 milligrams \[mg\] of caffeine). Strenuous activity is not allowed from 1 week prior to admission until the follow-up visit. * Are smokers within the previous 6 months * Have received treatment with biologic agents (such as monoclonal antibodies) within 3 months or 5 half-lives (whichever is longer)prior to dosing or have received a vaccination within 1 month * Have a history of multiple or severe allergies or has had an anaphylactic reaction or intolerability to prescription or non-prescription drugs or food * Are immunocompromised * Have had cancer or within the past 5 years * Have a history of significant allergies, in particular to ethanol or sensitivity to the fruits of capsicum plants (example: chili peppers) * Have eczema, scleroderma, psoriasis, dermatitis, keloids, tumors, ulcers, burns, flaps, or grafts on their forearm or other abnormality of the skin which may interfere with the study assessments * Cannot avoid excess tanning (any exposure to sunlight or a tanning bed which would cause a sunburn reaction) throughout the study and cannot cover forearms for 24 hours prior to treatment period * Have excessive hair growth on the volar surface of the forearm or subjects currently using lotions, oils, depilatory preparations, or other topical treatments on a regular basis which cannot be discontinued for the duration of the study; subject has used any topical treatments within 7 days of the start of the study